(en) Diversification of acorn worms (Hemichordata, Enteropneusta) revealed in the deep sea, par Karen J. Osborn, Linda A. Kuhnz, Imants G. Priede, Makoto Urata, Andrey V. Gebruk et Nicholas D. Holland, du Department of Invertebrate Zoology, Smithsonian Institution, National Museum of Natural History, Washington, DC, USA. Publié dans Proceedings of the Royal Society, Biological Sciences. 2011.